• Scalability
OPC UA can be used for devices of different performance classes:
– Sensors
– Embedded systems
– Controllers
– PC systems
– Smartphones
– Servers with MES or ERP applications.
The performance class of the devices is differentiated by profiles. Different OPC UA profiles
offer the possibility to scale OPC UA both for very small and simple devices as well as for very
powerful devices. An OPC UA profile describes functions and services that must be supported
by the server and the client. In addition, further functions and services that are not required
by the profile can be optionally provided.
Nano Embedded Device 2017 Server Profile
The "Nano Embedded Device 2017 Server Profile" from the OPC Foundation is available for
the smallest devices with severely limited functionality. This profile corresponds functionally
to the Core Server facet and defines the binary OPC UA TCP protocol as the required transport
profile. The profile permits connections without UA security, no subscriptions, and no
method calls. The support of diagnostic objects and variables is optional for this profile.
Other profiles are based on the "Nano Embedded Device 2017 Server Profile", require more
resources, and offer more functionality.
Micro Embedded Device 2017 Server Profile
This profile offers limited functionality, additional subscriptions/data monitoring, but no UA
security and no method calls. The profile requires at least two parallel connections.
3RW5 PROFINET High Feature communication module
The 3RW5 PROFINET High Feature communication module supports the "Micro Embedded
Device 2017 Server Profile" and additionally UA security.
• OPC UA uses security mechanisms at different levels:
– Establishing secure connections between an OPC UA server and an OPC UA client is only
possible if the client and server can log on using X.509-v3 certificates and mutually
recognize each other's certificates (application-level security). Various security policies
are possible, including an unsecured connection between server and client (security
policy: "No Security").
– For authorized access (authentication), a server can generally require the following
information from the user: A user certificate, user name and password, no legitimation of
the user.
The security mechanisms are optional and configurable.
Schema files used for OPC UA functionality
The OPC Foundation provides its users with schemas that manufacturers can use for server
implementations.
Functions
8.4 OPC UA server
SIRIUS 3RW5 PROFINET communication modules
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